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T O P I C R E V I E W

Robert Pearlman

Delta IV Heavy/NROL-49 launch from SLC-6

On January 17 20, at 1:08 1:10 p.m. PST (2110 GMT), a United Launch Alliance (ULA) Delta IV Heavy will launch the National Reconnaissance Office's NROL-49 satellite from Vandenberg Air Force Base in California.

The launch will be staged from Space Launch Complex-6 (SLC-6, pronounced Slick-six), the same pad once built for Department of Defense-dedicated space shuttle missions.

In the wake of the 1986 Challenger accident, SLC-6's use as a shuttle launch pad was cancelled, but a year earlier, Enterprise was brought out to conduct fit checks.

In their lead-up to covering the NROL-49 launch live from Vandenberg, Spaceflight Now has published a series of photo galleries documenting "The California space shuttle."

So check out these comprehensive photo collections that document Enterprise's time at Vandenberg beginning with a tour of the shuttle inside its hangar on North Vandenberg.

The shuttle then took a road trip over Vandenberg's hilly terrain and reached Space Launch Complex 6 for attachment to the external fuel tank and solid rocket motors at the pad.

Neat photos of Enterprise, but one question: Was the Canadarm mounted inside the orbiter the real deal or a facsimile?

Robert Pearlman

It appears to be a mock-up.

And as Spaceflight Now reports, officials have delayed the launch by three days. Liftoff has been reset for Thursday, January 20.

Robert Pearlman

Spaceflight Nowreports on the history of SLC-6 and its transition from being built to launch manned spacecraft to launching massive rockets.

Scheduled for the summer of 1986, the flight would usher in the Air Force space shuttle era, enabling large and valuable spy satellites to be carried into orbits around Earth's poles by the winged spaceplanes.

And it would bring the Navy captain's space career back to the place where he originally planned to leave the planet for space.

Two decades earlier, that very site was the launch pad for the Manned Orbiting Laboratory, a high-flying military reconnaissance space station.

But, remarkably, both projects were mothballed before Crippen ever got to blast off from the famed SLC-6 pad...

The largest rocket ever to launch from the West Coast of the U.S. carried a national security payload for the National Reconnaissance Office.

"The teamwork between the 30th Space Wing, the National Reconnaissance Office, United Launch Alliance and numerous other agencies was outstanding for our first-ever Delta IV HLV from Vandenberg Air Force Base," said Col. Keith Balts, 30th Space Wing vice commander and Launch Decision Authority. "I'm very proud to be part of the team who worked so hard to make this mission a success."

The Delta IV Heavy launched today is 235 feet tall and produced 2 million pounds of thrust.

The Delta IV Heavy, at 235 feet or approximately 23 stories tall, is the largest rocket ever to launch from the West Coast of the United States. The mission is in support of national defense.

Credit: ULA/Pat Corkery

"Today's launch was the second Delta IV Heavy launch for the NRO in two months and was also the largest rocket ever launched from the west coast," said Jim Sponnick, ULA vice president, Mission Operations. "Most important is the critical NRO payload launched today which will significantly enhance the effectiveness and safety of the brave men and women defending our nation every day. Today's successful launch represents the culmination of five years of hard work and exceptional skill in modifying the launch system to establish the west coast heavy lift capability for the nation and to integrate this important mission. I congratulate the combined NRO, Air Force, supplier and ULA team on this impressive accomplishment and successful launch."

The ULA Delta IV Heavy vehicle featured a center common booster core with two strap-on common booster cores. Each common booster core was powered by the RS-68 cryogenic engine producing 660,000 pounds of thrust. An RL10B-2 cryogenic engine powered the second stage. Both engines are built by Pratt & Whitney Rocketdyne. The payload was encased by a five-meter diameter (16.7-foot diameter), 63-foot composite bi-sector payload fairing. ULA constructed the Delta IV Heavy launch vehicle in Decatur, Ala.

The launch occurred after a multi-year construction effort to upgrade SLC-6 to accommodate the Delta IV Heavy. The last SLC-6 launch occurred Nov. 4, 2006, and was a Delta IV Medium, which launches one common core booster.

This was the fifth launch of a Delta IV Heavy in program history, with the four previous launches occurring at Cape Canaveral Air Force Station, Fla.

cspg

What's the nature of the material being shed off during ascent, at least up to first stage separation? Insulation?

apolloprojeckt

Nice launch, but is it normal that the flames they so high come up along the boosters?

Rocket Chris

The fire between left booster and main stage (almost top of left booster) during lift off isn't normal also... probably there was some gas streaming out of the engines and ignition was one second delayed.

But gee... they really burned up the isolation from the Delta. First time that I saw such flames!

Robert Pearlman

The flames (and resulting blackened insulation) is normal for this vehicle, as described in a 2005 Aviation Week article:

The Delta IV is the only launch vehicle that, by design, sets itself on fire during its ignition sequence.

Thousands of pounds of hydrogen are dumped through the vehicle's three RS-68 engines to condition their internal temperatures five seconds before oxygen valves are opened for ignition.

The hydrogen forms a cloud around the vehicle that is burned off spark generators to avoid an explosive hazard. This causes a huge ball of fire that blackens the core and the 125-ft. liquid strap-on boosters.

During climbout, free hydrogen continues to attach itself to the base of the vehicle, where it burns on insulation designed for that purpose. So while the fire is inconsequential, parts of the boattail remain ablaze until ascent into thinner air.

Heat emerging from RS-68 fuel turbine exhausts for roll control can also cause flame on the insulation as with the center engine just after liftoff. All of this looks frightening, but is normal.

MrSpace86

Quick question that I should know the answer to: Do the boosters and stages just crash back on land somewhere similar to Russian boosters?

garymilgrom

I believe the trajectory allows the boosters to fall into the pacific ocean, not onto land.

apolloprojeckt

But one question, is this rocket not powerful enough for a new type of space capsule for a space trip to the ISS? Or should be any longer, this series of rockets is still very reliable...

GACspaceguy

It is not about the power but is about being a "human-rated" vehicle. See this thread on that topic.

racso184

If anyone wondered how big the Delta-IV is, here's an interesting down to earth comparison:

Watching the launch of such a large rocket from "Slick-6" makes it much easier to visualise what it would have been like if the USAF got to fly the Space Shuttle from there. It would have been spectacular!

But did I read somewhere that studies done after the Challenger accident revealed a design-flaw in the launchpad that would have caused the shuttle to explode?

Jim Behling

quote:Originally posted by dom:But did I read somewhere that studies done after the Challenger accident revealed a design-flaw in the launchpad that would have caused the shuttle to explode?

No, it was a H2 explosion in the flame duct that could have damaged a shuttle.